22. Evolution of Populations

Antibiotic resistance in bacteria is an example of which of the following?

For several years, scientists have warned doctors of the danger of overprescribing antibiotics such as penicillin. Scientists are concerned because __________.

A population of squirrels is preyed on by small hawks. The smaller squirrels can escape into burrows. The larger squirrels can fight off the hawks. After several generations, the squirrels in the area tend to be very small or very large. What process is responsible for this outcome?

Birds with average-size wings survived a severe storm more successfully than other birds in the same population with longer or shorter wings. If severe storms occur regularly, then over time, one should expect these storms to bring about __________.

Which type of selection maintains stable frequencies of two or more phenotypic forms in a population?

Selection that acts over evolutionary time to preserve traits that increase an individual's ability to mate is known as __________.

Which statement below is true about sexual selection?

A number of mosquito populations today are resistant to insecticides that were once quite effective. Biologists think that insecticide resistance evolved in mosquitoes because __________.

Natural selection changes allele frequencies because some _________ survive and reproduce better than others.a. allelesb. locic. speciesd. individuals

The largest unit within which gene flow can readily occur is aa. population.b. species.c. genus.d. hybrid.

How do the phospholipids in archaea differ from those in other cells?a. They have tails made of unsaturated fatty acids instead of saturated fatty acids.b. They do not contain hydrocarbon chains.c. They have isoprenoid tails instead of fatty acid tails.d. They have two hydrocarbon chains instead of three hydrocarbon chains.

What two functional groups are bound to the central carbon of every free amino acid monomer?a. an R-group and a hydroxyl groupb. an N—H group and a ═(C═O) groupc. an amino group and a hydroxyl groupd. an amino group and a carboxyl group

Why isn't inbreeding considered an evolutionary process?a. It does not change genotype frequencies.b. It does not change allele frequencies.c. It does not occur often enough to be important in evolution.d. It does not violate the assumptions of the Hardy–Weinberg principle.

Describe three ways that evolution can occur via genetic drift.

Why is genetic drift aptly named? Select True or False for each statement.T/F It causes allele frequencies to drift up or down randomly.T/F It occurs when alleles from one population drift into another.T/F It occurs when mutations drift into a genome.